Ancenis (French pronunciation: [ɑ̃s.ni]; Breton: Ankiniz) is a former commune in the Loire-Atlantique department in western France. On 1 January 2019, it was merged into the new commune Ancenis-Saint-Géréon. It is a former sub-prefecture of the department, and was the seat of the former arrondissement of Ancenis.

It played a great historical role as a key location on the road to Nantes (23 miles to the southwest), the historical capital of Brittany. It was named "the key of Brittany" and the door of Brittany.

Historical population

Year Pop. ±% 1793 3,295 —     1800 2,923 −11.3% 1806 2,945 +0.8% 1821 3,888 +32.0% 1831 3,749 −3.6% 1836 3,667 −2.2% 1841 3,802 +3.7% 1846 3,824 +0.6% 1851 3,689 −3.5% 1856 4,198 +13.8% 1861 4,628 +10.2% 1866 4,148 −10.4% 1872 4,358 +5.1% 1876 5,177 +18.8% 1881 5,361 +3.6% 1886 5,544 +3.4% 1891 5,141 −7.3% 1896 5,048 −1.8%

Year Pop. ±% 1901 5,199 +3.0% 1906 4,998 −3.9% 1911 5,013 +0.3% 1921 4,222 −15.8% 1926 3,942 −6.6% 1931 4,040 +2.5% 1936 4,149 +2.7% 1946 4,815 +16.1% 1954 5,050 +4.9% 1962 5,102 +1.0% 1968 5,648 +10.7% 1975 6,997 +23.9% 1982 7,076 +1.1% 1990 6,896 −2.5% 1999 7,009 +1.6% 2006 7,407 +5.7% 2009 7,543 +1.8%

• Château d'Ancenis, a medieval and Renaissance castle
• The Loire river on which Ancenis is located (on the north bank)
• Church of Saint Peter, 15-16-17th century
• Chapel of the Ursulines
• Chapel Notre-Dame de Délivrance
• Old quarter with mediaeval houses
• Dolmen at Pierre-Couvretière

The soccer team is called RCA 44, (Racing Club D'Ancenis 44)

• Henri Ottmann, painter
• Jordan Veretout, French footballer
• William Louiron, footballer

Ancenis is twinned with both the town of Kirkham in Lancashire, UK and Bad Brückenau, a spa town in Bad Kissingen district, northern Bavaria which is situated in the Rhön Mountains in Germany.

• Communes of the Loire-Atlantique department
• Hortense Clémentine Tanvet Sculptor